A sample of a new cleaning product, \"Joe\'s Famous Bleach Cleaner,\" with a mas
ID: 483355 • Letter: A
Question
A sample of a new cleaning product, "Joe's Famous Bleach Cleaner," with a mass of 48.0 g , was diluted with an acetic acid solution containing excess I. A small amount of starch indicator solution was then added, turning the solution a deep bluish-purple. The solution was then titrated with 0.450 M sodium thiosulfate, Na2S2O3, containing the ion S2O32. A volume of 39.0 mL of sodium thiosulfate, the titrant, was needed to turn the solution colorless.
What is the percentage composition by mass of NaClO in the bleach product?
Explanation / Answer
What is the percentage composition by mass of NaClO in the bleach product?
moles S2O3 2- = 0.450 M x 0.039 L = 0.01755
moles I2 = 0.01755 / 2 =0.008775
= moles ClO-
mass NaClO = 0.008775mol x 74.4422 g/mol = 0.653g
% = 0.653 x 100/ 48.0 = 1.36 answer